The inverter will be in the input plus contactor and reactor is the normal configuration, the role of contactors relative to the power switch in the emergency use of contactors to directly stop the inverter power supply, plus reactor is to protect the rectifier block, The smoothing effect on the peak voltage.
The role of the output reactor is the frequency converter and motor distance far plus case, plus the contactor if it is a drag case is no need to add, and added no good in the inverter and the motor is a drag two one With a prepared case is the need to add the contactor to convert the motor, when doing the control needs to let the contactor action after the suction, the use of contactor normally open contact as the inverter running one of the conditions.

Power supply side contactor Purpose of use: Once the power supply is disconnected, the inverter will be disconnected from the power supply automatically to prevent the inverter from working when the external terminal is in control state to protect the safety and personal safety of the equipment. Inverter internal protection Function, the inverter is disengaged from the power supply via the contactor.

When using, please do not use the magnetic contactor to start or stop frequently (the opening and closing life of the inverter input circuit is about 100,000 times), can not stop the inverter with the electromagnetic contactor on the power supply side to select the appropriate reactor and frequency conversion Can suppress the harmonic current, reduce the total amount of harmonics generated by the inverter system, improve the power factor of the inverter, and can suppress the impact of the inrush current from the power grid on the inverter, protect the inverter and reduce the power consumption of the inverter. Motor noise. To ensure the reliable operation of the inverter and the motor.

Line reactor LA1 connected between the power supply and inverter, it can limit the sudden change in voltage and operating voltage over-voltage caused by the impact of current, effective protection of the inverter to improve the inverter power factor, inhibit the inverter input power grid harmonics Current, a significant reduction of 5,7,11,13 harmonic.
The main purpose and function of the output reactor is to compensate for the influence of the distributed capacitance of the long line and to suppress the harmonics component of the general frequency conversion output, so as to reduce the noise of the inverter. The output choke is located close to the output of the frequency converter and the motor to compensate for distributed parasitic capacitance between the motor and its cables relative to and relative to one another, thereby extending the length of the motor cable. In general, the general inverter manufacturers are allowed to connect the motor cable is the maximum length of the provisions should be used in accordance with the provisions of the product specification wiring.

1, Input Reactor Line reactor: input reactor can suppress the harmonic current, improve the power factor and weaken the input circuit in the surge voltage, current impact on the inverter, weakening the impact of the power supply voltage imbalance, under normal circumstances, Must be added to the line reactor.

If the inverter front end, there are separate power transformer winding, you can not add line reactor; if the front of the inverter, there is no separate power supply for the transformer winding, you must add line reactor, otherwise, Will affect the normal operation of the inverter.

2, Output reactor output reactor: When the inverter output to the motor cable length is greater than the product specifications, should increase the output of the reactor to compensate for the motor long cable running coupling capacitor charge and discharge effects, to avoid over-current converter. There are two types of output reactors, one output reactor is a core-type reactor, when the carrier frequency of less than 3KHZ frequency converter used. Another output reactor is a ferrite type, when the carrier frequency of less than 6KHZ frequency converter used. The output choke is designed to increase the distance between the inverter and the motor. The output choke can effectively suppress the momentary high voltage generated by the IGBT switch of the inverter and reduce the adverse effect of this voltage on the cable insulation and the motor. . At the same time in order to increase the distance between the inverter to the motor can be appropriate to thicken the cable to increase the insulation strength of the cable, try to use non-shielded cable.

3, the input side plus the contactor, as long as the frequency is not frequent on-off threat. The output end will add the contactor, the output end will have the overvoltage (the electrical machinery inductive load) when the end opens acts on the power module, although has the absorption circuit to prevent the overvoltage, causes the breakdown not to be inevitable, but should avoid. So do not add is the best, even if you want to add to stop the output in the inverter can be disconnected, but also to do when the output chain to prevent the inverter connected, otherwise the high current will burn IGBT.